It is common knowledge that water moves through the soil in two ways: 1) downward pulled by gravity and 2) outward and upward, pulled by capillary action. It is also a common knowledge that the plant hydrotropism is the growth or turning of plant roots toward or away from moisture in the soil. The response can be positive towards the water or negative away from the water. Roots, for instance, are positively hydrotropic. That means that they grow towards moist soils to avoid drought stress. Once a root cap has sensed water, it bends and then the root grows towards it. However, as an underground system, there would be difficulty and no efficient way to monitor the system performance for each tree and the devices would not have any protection from clogging and many other problems. As Rogers, D. H. and F. R. Lamm pointed out in their paper that clogging of drip line emitters is the primary reason for SDI system failure (2005. Key considerations for a successful subsurface drip irrigation (SDI) system. In proceedings of the Central Plains Irrigation Conference, Sterling, Colo., Feb. 16-17, 2005. Available from CPIA, 700 N. Thompson, Colby, Kans. pp. 113-118).
Underground irrigation has showed so many advantages and become so important in horticulture and agriculture compared with above ground irrigation, therefore great efforts have been made to develop various devices or systems for establishing true underground irrigation. For example, several US patents and published patent applications have detailed both the advantages related to underground irrigation and disclosed various underground devices. Such as U.S. Pat. No. 4,453,343, issued to Grimes for “Irrigation system” U.S. Pat. No. 5,938,372 issued to Lichfield for “Subsurface irrigation apparatus and method”; U.S. Pat. No. 6,540,436 issued to Ogi for “Deep root watering unit”. Some other specific invention aimed and focused underground irrigation with special disclosures. Such as U.S. Pat. No. 6,443,367, issued to Bova for “Deep watering device”; U.S. Published Patent Application No. US 2003-0196375 A1, filed by Ferro for “Method of producing deep-rooted trees for phytoremediation applications”; U.S. Pat. No. 5,996,279, issued to Zayeratabat for “Plant irrigation apparatus”; U.S. Pat. No. 4,003,408, issued to Turner for “Underground irrigation porous pipe”; U.S. Pat. No. 8,381,437, issued to Ciudaj for “Irrigation device and method of promoting deep root growth plant” and recent U.S. Pat. No. 9,485,923, issued to Ensworth for “Elastomeric emitter and methods relating to same”.
ZigBee is a specification for a suite of high level communication protocols using small, low-power digital radios based on the IEEE 802.15.4-2003 standard and ZigBee PRO, also known as Zigbee 2007, the enhanced ZigBee Pro Specification, for wireless personal area networks (WPANs), such as wireless headphones connecting with cell phones via short-range radio. The technology defined by the ZigBee specification is intended to be simpler and less expensive than other WPANs, such as Bluetooth. ZigBee is targeted at radio-frequency (RF) applications that require a low data rate, long battery life, and secure networking. These features will be the potential application for ZigBee technology with various demand for individual device and further solve many practical difficulties. U.S. Pat. No. 8,644,166, issued to Xia, et al, for example, disclosed that a sensor device integrates ZigBee® technology into power switch device to provide monitoring and control of power usage, as well as operational control of connected devices.
Zigbee provides a cost breakthrough that means wireless technology can be more widely deployed in wireless control and monitoring applications: Zigbee power requirements are so low that devices can have extremely long battery life and use smaller “coin cell” type batteries; A Zigbee node can wake up, check in, send data, and shut down in less than 30 ms; ZigBee is an open standard that is supported by a large number of vendors and many others. Especially the feature of the address used for each individual ZigBee End Device provides a very suitable way for the combination with each individual UIFR device for the purpose to monitor the UIFR device and plants at real time and real location, since no two devices can have the same IEEE address in the entire world.
As we described in our patent (U.S. Pat. No. 8,786,407), Radio frequency identification (RFID) technology and RFID related knowledge have been widely used in the world, since the first true ancestor of modern RFID Patent (U.S. Pat. No. 3,713,148) to Cardullo, et al. in 1973 and the first patent associated with the abbreviation RFID was granted to Walton, et al. in 1983 (U.S. Pat. No. 4,384,288). Recent U.S. Pat. No. 7,928,965 to Rosenblatt, et al, a RFID chips in Apple's iOS devices that will enable such things as wireless transfers of data from an iPhone to a desktop with just a simple shaking motion or even allow a user to open up a keyless home or car door with a simple swipe.
A RFID tag not only provides the unique identification number, also it can be read within a certain range wirelessly. This special advantage can really help to solve the problem that a ZigBee End Device can't be read, even though you personally face it or hold the ZigBee End device in your hand, except read them via a network system.
These above cited references teach some common features, disclose irrigation systems or specific devices that attempt to provide underground irrigation, data collection and remote control technology. However, these references, on the other hand, revealed that there still are many problems related to underground irrigation, of which made the underground irrigation still to be difficult and even impossible. These limitations and related problems, for example, are listed as the followings:
1. Nearly all cited patents are still use high pressure to force the water into the soil via all kind of their designed devices;
2. None of these disclosures shows a method how to make the underground irrigation to be visible or to be hearable, or the water volume in an individual device can be measurable at a real time and real-location manner;
3. None of these cited patents or patent applications showed that the underground irrigation device can be changeable or repairable without digging if the underground irrigation device is damaged;
4. None of these cited patents teaches an efficient and convenient way how to monitor and how to remote control each individual underground irrigation device or a group of underground irrigation devices and how to collect data from each individual or a group of underground irrigation devices;
5. None of these cited patents does consider how to use underground irrigation device to help underground soil and plant root respiration, especially how to use underground irrigation device to obtain enough fresh air for plant roots and soil respiration. Plant and soil respiration is an important issue, as important as irrigation and fertilization, because plant root respiration directly affects plant growth and fruit yield;
6. None of these issued patents or published patent applications provides an universal unique label used for each individual underground irrigation device and the plant. Furthermore, the universal unique label can be read by a RFID reader or a barcode reader or can be read in person directly;
Still there are more other issues directly or indirectly related to the underground irrigation, fertilization and plant respiration, which are beyond our scope of the present patent application.